Grid structure for electron discharge devices



I Jan. 25, 1949.

s. WESTON GRID STRUCTURE FOR ELECTRON DISCHARGE DEVICES 3 Sheets-Sheet 1 Filed March 25, 1945 INVENTOR. S/IVEO/V mssrozv BY Z ATTORNEY Jan. 25, 1949.

' GRID STRUCTURE F Filed March 23, 1945 s. WESTON 2,459,859

OR ELE CTRON DISCHARGE DEVICES I 5 Sheets-Sheet 2 v v "INVENTOR. I 5/ /60 WESTON ATTORNEY Jan. 25, 1949. s. WESTON 2,459,859

GRID STRUCTURE FOR ELECTRON DISCHARGE DEVICES Filed March 23, 1945 3 Sheets-Sheet 5 I N V EN TOR. ammo/v WESTON ATTORNEY Patented Jan. 25, 1949 2,459,859 GRID STRUCTURE FOR ELECTRON DISCHARGE DEVICES Simeonwe ston, New York, to eral Telephone and Radio Cor oration, N'v'v York; N. Y., a corporation of Delaware Application March 23, 1945, Serial No. 584,422 10 Claims. (01150 2715) 1 2 The present invention relates to electron dis- Referring now particularly to 1 g. 1 charge devices. drawings, the electron discharge device has an An object of the present invention is the proenvelope generally designated by the tunnel l vision of an improved electron discharge device. including insulating portions 2, 3 and Lt -ljii'ch Another object of the present invention is the 5 are sealed conductive dis-' cs 5, 6-, I provision of an improved electrode assembly for 8 depending from and integral with disc 1, and a electron discharge devices and particularly one reentrant metallic elosure member 9.

adapted to be mounted on a disc extending oiit- Disci d serves as the ijpper of wardly through the envelope of the device and the tube and is sealed to one end oi nsulat ng serving as an external grid terminal. 10 portion 2. Disc 5 also serves asthe anode term Another object of the present invention is the inal I and support, 1's providfd with provision of an improved grid assembly and pre sed or dished pertionio at the center thereof mounting therefor which provide good heat distothe bottom of which 'is' welded meanest H;

sipation, and thereby maintain the grid at a Disc '6 is sealed between insulatingportions reiatively low temperature, thus minimizing grid 2 and 3 and serves the ic'ter'nal grin t'efifi an emission. A and grid assembly mount. A rectangular ope Another object of the present invention is the ing 12 is iormed within discli, and adjacen' said provision of an improved grid assembly wherein opening the discli is provided with a a the grid wires are kept taut under tension so portion [3 having a plurality off inte as to maintain exact spacing between the grid threaded. holes 14 threin 'Ihe grid wires themselves as well as between the grid wires [5 (see Figs. through 6) which is mount and other electrodes. disc 6; consists of a relatively thick conduc ye Still another object of the present invention plate i 6 ofgood conductive mater al and pre ris the provision of an improved electrode assemably somewhat resilient, on the IT, bly and mounting whereby the electrode may be consisting of a plurality of relatively thin wires readily and accurately mounted within an elec- I8, is inounteda'nd supported said grid wires tron. discharge device. being of conductive material, preferably nickel Other and further objects of the present invenor lnolybdenum. p p A tron will become apparent and the invention will W The grid assembly I5 is preferably made in the be best understood from the following description 3 following way; h I h of an embodiment thereof, reference being had Arectangular opening is is formed in the mid; to the drawing. in which: g V V dle of the plate and flanges 20 are bent upward Fig. 1 is an enlarged sectional view of an elecfrom said plate substantially normal thereto and tron discharge device embodying my invention; at opposite ends of said opening. The height of Figs. 2 and 3 are sections taken substantially said flanges determines the positioning of the along the lines 2-2 and 33 respectively of Fig. grid, aswill beapparent from the subsequent de- 1; scription; and it may be necessary to machine. the Fig. 4 is a detailed view of the grid assembly; tops 2| pf said flanges toobtain the precise height d required; The plateis then curved or bent as ii- Figs. 5 and 6 are similar detailed views of the 40 lustrated in Fig. 4. The grid l1; consisting of its grid assembly as it is being mounted on the grid plurality of grid wires 18, is then welded or brazed disc. v to the tops 2| of said flanges. Any suitable braz= Referring now to the drawings, the electron dising material may be employed for brazin'g th'grid charge device or tube illustrated is similar in to the tops 2|; Agold copper allbyhas-been found many details to the tube described and claimed satisfactory for this purpose; in the copending application of J. Glauber-l, for i 'The grid Wires l8 are not pulled taut when Assembly for electron discharge device, Serial they are brazed to the tops 2| but are relativelfy No; 542,089, filed June 26, 1944, and the present loose or somewhat slack and notundr arisen. invention maybe considered in one aspect as beifs-pull saidgrid wires taut and bring thei'ii are me an improvement thereon. der tension, the plate ls which is mam stage, is placed under pressure and bent into a substantially flattened configuration.

Plate It may be flattened and mounted in one operation by inserting said plate inside the envelope l of the tube so that the plate l6 touches the thin portion 13 of disc 6 (see Figs. 1 and inserting screws 22 through suitable holes 23 in plate 16 and threading said screws into the internally threaded openings I4 of the thin portion l3. As will be clear from Fig. 5, as the screws 22 are tightened, the plate 16 is flattened, thus bringing the grid wires I18 under tension and at the same time mounting the grid assembly and accurately positioning the grid within the tube.

If desired, as for example to avoid too much strain on the threads of screws 22 and opening 14, plate It may be partially straightened out prior to insertion in the envelope. This may be done in a vise or in any other suitable fashion. The final straightening may then be accomplished by screws 22.

Because of the flattening of member IS, the grid wires will be maintained under tension and will not sag. Furthermore, it will be seen that because of the relative thickness of plate said plate will quickly conduct heat from the grid to disc 6 which will, in turn, dissipate said heat outside the tube envelope.

Disc! may be used as the cathode terminal and, together with its skirt 8, serves to support a cathode mount 24 of the type described in the aforesaid J. Glauber-l application. The cathode mount 24 consists of a conductive frame 25 having insulating spacers 26 mounted at opposite ends thereof and secured by eyelets 21. The spacers 26 are provided with openings 28 therein in which is inserted a cathode sleeve 29 having a heater 30 therein. The heater 3D is connected by flexible leads 3! to lead wires 32 extending through and sealed in the insulating portion 4 at the bottom of the tube. The cathode sleeve 29 has a small tab 33 struck therefrom and bent adjacent to and welded or brazed to a similartab 34 from the conductive frame 25. This forms a direct current connection between the cathode sleeve and the frame 25 which has low thermal conductivity. A low impedance high frequency connection between said sleeve and said frame is produced by the inherent capacity therebetween.

Frame 25 of mount 24 is fastened at its lower end, as by welding, to a relatively stiff metallic member 35 which is in turn fastened to the skirt 8. The mount 24 is further maintained in position by shoulders 36 formed in ,the upper corners of the spacers 26 which shoulders bear against the bottom and sides of the portions of disc 6 adjacent opening l2.

The tube is preferably assembled in the following order: I

After discs 5, 6, and I with its skirt 8, have been sealed to insulating portions 2 and 3 and the anode ll mounted on disc 5, the grid assembly is then put in place as hereinbefore described. Next the mount 24 carrying the cathode sleeve 29 and heater 30 is inserted and secured in place by means of member 35. The leads 3| from the heater are fastened to lead wires 32. Then the assembly consisting of insulating portion 4 and reentrant closure member 9 is inserted and secured in place as by means of brazing at the point indicated by numeral 31. The tube is then evacuated through stem 38 and otherwise treated in the manner well-known in the art.

While I have described details of a grid assembly and mounting and a process therefor,

it wil1 be seen that much of this may be employed for other electrodes. Accordingly while I have described above one structure and the specific details of a process embodying my invention, it is to be clearly understood that this description is made only by way of example and not as a limitation on the scope of my invention as defined in the accompanying claims.

I claim:

1. An electrode structure for an electron discharge device comprising a bent plate, a. multistrand electrode mounted on said plate, a mount for said plate and said electrode and means holding said plate in an altered shape against said mount for bringing 2. An electrode structure for an electron discharge device comprising a curved conductive plate provided with an aperture, flanges extending from said plate, an electrode extending across said opening on the concave side of said plate and secured to said flanges, and means holding said plate in a straightened shape to bring said electrode under tension.

3. An electron discharge device having an envelope and a conductive disc extending outwardly through the envelope and forming an external terminal, said disc having an opening therein within the envelope, a curved conductive plate within the envelope having an opening therein, a pair of flanges extending from said plate adjacent its opening, a planar grid extending across the plate opening on the concave side of said plate and secured to said flanges, and screw means fastening said plate to said disc in a flattened shape for bringing said electrode under tension.

4. An electron. discharge device having an envelope, and a metallic disc partially within the envelope and extending through and sealed in said envelope and forming an external connector, said disc having an opening therein within the envelope, a conductive plate within the envelope having an opening therein, a pair of flanges extending from said plate, said plate being normally curved with said flanges on the concave side, a planar grid extending across the opening of said plate on the concave side thereof and secured to said flanges, and means fastening said plate in straightened position to said disc with the opening of said plate within the opening of said disc.

5. A grid structure for an electron discharge device comprising a bent conductive plate having an opening therein and a concave side, a grid extending across said opening and secured to said plate on said concave side, a mount for said grid and plate, and means securing said plate to said mount, said plate being straightened against said mount for bringing said grid under tension.

6. The method of making an electrode assembly comprising mounting the electrode on the concave side of a curved support and straightening said support to bring said electrode under tension.

7. The method of making a grid assembly comprising forming an opening in a conductive member, bending said member, mounting an electrode on the concave side of said member extending across said opening, and straightening said member to tauten said electrode.

8. The method of making an electrode assembly comprising forming an opening in a flat conductive plate, forming flanges extending angularly to the plane of said plate, bending the plate so that the surface from which the flanges project is substantially concave, mounting the elecsaid electrode under tension.v

trode on said flanges and straightening the plate to bring the electrode under tension.

9. A method of mounting an electrode in an electron discharge device envelope having a mounting member therein comprising mounting said electrode on the concave side of a support having a given configuration, and inserting said support inside the envelope adjacent said mounting member and forcing said support against said mounting member to flatten said support and bring said electrode under tension.

10. A method of mounting a grid in an electron discharge device envelope having a disc sealed to the envelope, said disc having an opening therein within the envelope, comprising mounting the grid on the concave side of a curved metallic plate, inserting the plate inside the envelope adjacent said disc with the grid aligned with the opening of said disc and forcing the plate under tension against the disc.

SIMEON WESTON.

REFERENCES CITED The following references are of record in the Iiie of this patent:

UNITED STATES PATENTS Number Name Date 841,387 De Forest Jan. 15, 1907 1,613,948 Hartley Jan. 11,1927 1,958,591 Roberts May 15, 1934 1,983,838 Bowles Dec. 11, 1934 2,012,038 Eitel et a1 Aug. 20, 1935 2,182,968 Lunsford Dec. 12, 1939 2,183,635 Barker Dec. 19, 1939 2,194,551 Holman Mar. 26, 1940 2,197,526 Kosack Apr. 16, 1940 2,367,332 Bondley Jan. 16, 1945 2,397,233 Bingley Mar. 26, 1946 2,411,522 Chevigny Nov. 26, 1946 FOREIGN PATENTS Number Country Date 528,588 Germany July 2, 1931 l Disclaimer New York, N. Y. GRID STRUCTURE FOR ELECTRON Patent dated J an. 25, 1949. Disclaimer filed 2,459,859.Sime0n Weston,

Federal Telephone and Radio Goa-pom- DISCHARGE DEVICES. Mar. 9, 1951, by the assignee,

te'on. Hereby enters this disclaimer 'to claims 1 to 8, inclusive, of said patent.

[Ofiictal Gazette April 24, 1951.] 

